支撑板孔径对7A04-T6铝合金板冷挤压后孔周环向残余应力分布的影响  

Effect of Backing Plate Hole Diameter on Residual Stress Distribution around 7A04-T6 Aluminum Alloy Hole after Cold Expansion

作　　者：张飞[1] 何宇廷[1] 张腾[1] 邵青[1] 李培源[1] 

机构地区：[1]空军工程大学航空航天工程学院,西安710038

出　　处：《机械工程材料》2015年第9期89-93,共5页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(51475470)

摘　　要：使用非线性有限元软件建立了含孔7A04-T6铝合金板的开缝衬套冷挤压模型,模拟了开缝衬套冷挤压过程,对冷挤压后孔周环向残余应力的分布进行了预测,并与实测结果进行对比,最后探讨了不同支撑板孔径下冷挤压后孔周环向残余应力的分布。结果表明:孔周环向残余应力的模拟结果与实测结果较为吻合;随着支撑板孔径增大,板件入口层处残余压应力有增大的趋势;当支撑板孔径小于11.74mm时,在孔边出口层会形成明显的凸台,造成残余压应力突变,出口层残余应力峰值出现在支撑板孔边所在处;随着支撑板孔径增大,板件出口层环向残余应力逐渐趋向平滑,凸台现象逐渐减缓。A split sleeve cold-expansion model of 7A04-T6 aluminum alloy plate with hole was carried out with a finite element software, the split sleeve cold-expansion process was simulated, the hoop residual stress distribution around the hole after cold expansion was predicted, and the prediction results was compared with the measured results. The hoop residual stress distribution around the hole after cold expansion at different backing plate hole diameters was discussed finally. The results show that the simulated residual stresses around the hole was accordance with the measured results. The residual compressive stress in the entrance layer of the plate exhibited an increase trend with the increase of the backing plate hole diameter. When the backing plate hole diameter was smaller than 11.74 ram, lug boss was formed in the exit layer, which lead the residual compressive stress changed sharply, and the residual compressive stress peak in the exit layer located in the backing plate hole edge. The hoop residual stress tended to change more smoothly with the increase of the backing plate hole diameter, and the lug boss vanished gradually.

关 键 词：7A04-T6铝合金 支撑板孔径 冷挤压 残余应力 

分 类 号：V261.2[航空宇航科学与技术—航空宇航制造工程]